Lack of a screw thread and odd bar thickness means that you must use decathlon weights and collars which makes the bar incompatible with other weight systems that you might already be using or may want to add to it
Response from Sport Leader
Thank you for your valuable rating and comments. Your review is important to us in helping us to motivate us to strive for outstanding product quality.
The curl bar is 28mm in diameter, which is a standard weight bar size, while olympic bar is 50mm. Weight plates compatible with our Decathlon Weight Training Curl Bar are available on various online fitness shops.
We are looking forward to seeing you again in the store. If you have any further questions, please do not hesitate to contact us. Good day!
Decathlon Hong Kong Fitness Team